Why is this the right answer? Please really motivate so it's understandable, thanks.

STUDENT StudentID StName 1 Pericles 2 Alexander 3 Ptolemy 4 Euclid Pythagoras Aristotle Supervisor ID Project Grade 1 5 1 5 2 NULL 3 4 2 3 2 4 SUPERVISOR SupervisorID SupName 1 Thor 2 Marcus 3 Magnus 4 Caesar Question 10 Consider we want to get a list of the () IDs and (ii) names of the supervisors that actually supervise students. Which of the following statements will give this answer? B Select SupervisorID, SupName From SUPERVISOR; Select Distinct SupervisorID, SupName From SUPERVISOR Left Join STUDENT on STUDENT. Supervisor ID-SUPERVISOR. SupervisorID; Select Distinct SupervisorID, SupName From STUDENT, SUPERVISOR Where STUDENT. Supervisor ID-SUPERVISOR.SupervisorID; D Select Distinct SupervisorID, Supllame From SUPERVISOR Where STUDENT. Supervisor ID-SUPERVISOR.Supervisor ID; Answer C Question 11 Which of the following statements will retum the amount of supervisors that are actually supervising students from table STUDENT? Select Distinct COUNT(*) From STUDENT, SUPERVISOR Where STUDENT. Supervisor ID-SUPERVISOR.SupervisorID; Select COUNT (Distinct SUPERVISOR. SupervisorID) From STUDENT, SUPERVISOR Where STUDENT. Supervisor ID-SUPERVISOR. SupervisorID; Select COUNT(SUPERVISOR.SupervisorID) From SUPERVISOR Left Join STUDENT on STUDENT. Supervisor ID-SUPERVISOR. SupervisorID; Select COUNT(*) From SUPERVISOR; AnswerB